TWI682648B - Method and devices for negotiating bandwidth in a peer-to-peer network - Google Patents

Abstract

The present invention relates to distributing bandwidth between a plurality of devices (702a-c) in a system having bandwidth limitations, and in particular to a method for negotiating bandwidth in such a system wherein the plurality of devices (702a-c) are interconnected in a peer-to-peer network (200). The present invention further relates to a computer program product implementing the method and to such devices (702a-c).

Description

Method and device for negotiating bandwidth in point-to-point network

The present invention relates to distributing bandwidth among a plurality of devices in a system with a bandwidth limitation, and specifically relates to a system for interconnecting the plurality of devices in a point-to-point network The method of negotiating bandwidth. The invention further relates to these devices and to a computer program product implementing the above method.

It is common to have multiple devices each requiring bandwidth in a system with bandwidth limitations. An example of this system is a monitoring system that includes one of 10 monitoring devices. The total bandwidth available in the monitoring system can be, for example, 100 Mbit/s. In these systems, it is known to manually set a bandwidth upper limit for each monitoring device by, for example, assigning a bandwidth upper limit of 10 Mbit/s to each monitoring device so that the total bandwidth upper limit of one of the monitoring devices does not exceed 100 Mbit/ s limit. In this case, each monitoring device will usually have its own bit rate controller, which can be set to adjust the encoding of the monitoring data to be transmitted obtained by the monitoring device so that it does not exceed the assigned 10Mbit/s limit. The bit rate of the monitoring data can be reduced by encoding the monitoring data using a higher compression ratio or by discarding the bits of the monitoring data (for example, skipping the frame in an image stream). When the bit rate of the monitoring data decreases, one of the bit rates for the monitoring data decreases and increases compared to the bit rate that would be required to transmit the originally acquired monitoring data. However, depending on the monitoring data obtained by the monitoring device, it may be advantageous to adapt the upper limit of the bandwidth so that the bit rate of the encoded monitoring data can be lowered or higher. This need can be Adjust the upper limit of the bandwidth of the monitoring device.

US 2012/0218416 (Thales) relates to a dynamic reconfigurable video surveillance system including at least one video camera, a remote server, and at least one observation terminal. The video camera or cameras include components for compressing the captured video sequence, and the compression ratio can be dynamically adjusted by considering a control message originating from the remote server. The control message may include a priority associated with each video stream received from the camera or cameras of the system through a remote server. The remote server determines based on the signaling information indicating the activity detected by the video camera or cameras and forwarded to the remote server, or the priority of each of the video cameras. This system 100 is schematically depicted in FIG. 1, where the remote server 102 can send control messages to any of the video cameras 104a to 104d for adapting the compression ratio to be used by the video cameras 104a to 104d. The control message may depend on the priority calculated by the video camera and on the activity detected by each of the cameras. These priorities are transmitted from the video cameras 104a to 104d to the remote server 102.

However, the video surveillance system in US 2012/0218416 is complicated and does not consider the situation in which all or many video cameras have a high priority.

In view of the above, one objective of the present invention is to solve or at least reduce one or more of the disadvantages discussed above. Generally speaking, the above objectives are achieved by the accompanying independent patented technical solutions.

According to a first aspect, the invention is implemented by a method for negotiating bandwidth in a system including a plurality of devices interconnected in a point-to-point network, wherein each of the plurality of devices has a Adjust the upper limit of the bandwidth. The method includes the following steps: calculating a ranking score of one of the requesting devices indicating a priority to increase one of the upper limit of the bandwidth of the requesting device at one of the plurality of requesting devices; Sending to one or more remaining devices of the plurality of devices; and receiving one or more answers from the one or more remaining devices at the requesting device.

Each of the one or more answers corresponds to a respective one of the one or more remaining devices and includes a ranking score of the remaining devices that describes a priority that maintains a priority of the bandwidth upper limit of the remaining devices.

The method further includes determining at the requesting device based on the ranking score of the requesting device and the ranking score of the one or more answers from one or more remaining devices corresponding to the one or more received answers One device of bandwidth.

The method further includes increasing the upper limit of the bandwidth of the requesting device and decreasing the upper limit of the bandwidth of the determined device from which the receiving bandwidth is received.

In the context of this description, the term "bandwidth" should be understood as a capacity used to transmit and/or receive data at a device. In other words, the bandwidth indicates the available bit rate capacity, where the bit rate can be defined as the amount of data transmitted/received per unit of time. The "bandwidth upper limit" of a device therefore describes the maximum capacity of this device for transmitting and/or receiving data at that device. It should be noted that the total capacity or bandwidth limit of one of the entire system can be limited not only by the actual network capacity of the system but also by, for example, one of the storage solutions of the system.

In the context of this description, the term "point-to-point network" should be understood as a decentralized network in which interconnected devices are able to send and receive messages among each other without using a centralized management system or server.

One of the advantages of the present invention is to dynamically negotiate the upper limit of the bandwidth of individual devices. By dynamically determining the upper limit of the bandwidth of individual devices, one can more wisely use the total bandwidth budget of one of the systems without exceeding the actual bandwidth limit of the entire system.

By interconnecting the devices of the system in a point-to-point network, the need to deal with one of the servers in bandwidth negotiation is removed. Therefore, a more cost-effective system can be achieved.

Based on the ranking score of the requesting device and the ranking score of one or more answers, one of the advantages of the device that should receive the bandwidth from the devices of the system is that a well-proven decision can be made. For example, the determined device may be a device having a lower ranking score than the ranking score of the requesting device. According to some embodiments, the determined device may be The device with the lowest ranking score among the devices receiving the answer. According to some embodiments, if all the received answers include a ranking score higher than the ranking score of the requesting device, the device from which the bandwidth is received is not determined and therefore the bandwidth upper limit of the requesting device is not increased.

By increasing the upper limit of the bandwidth of the requesting device, and at the same time reducing the upper limit of the bandwidth of the determined device from which it receives the bandwidth, the risk of exceeding the actual bandwidth limit of the system is reduced. Advantageously, the upper limit of the bandwidth of the requesting device is increased by the same amount as the lower limit of the bandwidth of the determined device from which the bandwidth is received.

According to some embodiments, the request for additional bandwidth is a broadcast message in one of the peer-to-peer networks. Therefore, the requesting device does not need to record the number of devices connected to the system via a peer-to-peer network and the identifiers (IP addresses or the like) of these devices.

According to some embodiments, the request for additional bandwidth includes an identifier of the requesting device, and each of the one or more answers is a unicast message in a peer-to-peer network. Therefore, the data traffic and computing load in the peer-to-peer network are reduced compared to the case where each answer is a broadcast message.

According to some embodiments, the step of increasing the bandwidth upper limit of the requesting device includes increasing the bandwidth upper limit by a predetermined amount, and the step of decreasing the bandwidth upper limit of the determined device includes decreasing the bandwidth upper limit by the predetermined amount. According to this embodiment, the bandwidth reallocation will be performed in the iterative step, which may be advantageous because the reallocation may be finer. If, after the upper limit of the bandwidth of the requesting device has been increased by a predetermined amount, the requesting device requests a further increase, the result of this request may be different from the first request because the ranking scores of the requesting device and the device answering the request may change. Therefore, if the requesting device receives bandwidth from the first one of the remaining devices for the first time and then sends a further request, this time the bandwidth may be received from a different one of the remaining devices or may not be received from the remaining device. In addition, one of the further advantages of this embodiment may be to request a reduction in the computational complexity at the device, because there is no need for computation to increase/decrease the amount of bandwidth upper limit of the device of interest.

According to some embodiments, the method further includes the following steps: calculating the requesting device The difference between the ranking score and the ranking score corresponding to the answer of the decided device from which the bandwidth was received; and based on the calculated difference, calculate an amount of the bandwidth received by the requesting device from the decided device, where the increase The step of requesting the bandwidth upper limit of the device includes increasing the bandwidth upper limit by the calculated amount of bandwidth, and wherein the step of decreasing the bandwidth upper limit of the determined device includes decreasing the bandwidth upper limit by the calculated amount of bandwidth. One advantage of this embodiment is that a device with a lower ranking score can receive more bandwidth than a device with almost the same ranking score. This can further improve the efficiency and accuracy of the bandwidth negotiation method.

According to some embodiments, each of the one or more answers further includes a value indicating an excess bandwidth at the remaining device corresponding to the answer, and wherein the one or more received answers are determined at the requesting device The step corresponding to one of the one or more remaining devices from which the bandwidth is received is further based on a value indicating one of the excess bandwidth of the one or more answers. One advantage of this embodiment is that even if a device has a higher ranking score than other devices that receive answers from it, it can still receive unused bandwidth from the device. In other words, a device that has a low ranking score but utilizes all of the bandwidth specified to it via the upper bandwidth limit (ie, does not have the excess bandwidth specified) has a higher presence than the device actually uses for transmission and/or reception In the case of another device with an upper bandwidth limit (that is, a designated excess bandwidth), the data may not be determined as the device from which it receives the bandwidth. In this case, the bandwidth can be received even from a device having a higher ranking score than the ranking score of the requesting device.

According to other embodiments, the answer does not indicate a surplus bandwidth but instead calculates a ranking score for a surplus device based at least in part on the surplus bandwidth. A further alternative example on which the ranking score of a remaining device is calculated will now be described.

According to some embodiments, at least one of the following is used to calculate the ranking score of a remaining device: ˙ indicates a value of the excess bandwidth of one of the remaining devices, ˙ the upper limit of the bandwidth of the remaining device, ˙ One of the importance parameters of the remaining devices in the system including a plurality of devices, ˙ a time scheduling parameter, ˙ a historical parameter related to the previous ranking score of the remaining devices.

The importance parameter may reflect a parameter manually input from a user, for example, indicating that a particular device is important and therefore should always have a high-frequency bandwidth upper limit compared to the upper-frequency bandwidth limit of other devices in the system.

If a specific device is more important or less important than other devices in the system during a specific time of the day, during the weekend, etc., then the scheduling parameters can be used. Other possible parameters or values for determining the ranking score of a remaining device will be described below.

According to some embodiments, at least one of the following is used to calculate the ranking score of the requesting device: a parameter indicating a quantity of the missing bandwidth at the requesting device, the upper limit of the bandwidth of the requesting device, and a system including a plurality of devices One of the importance parameters of the requesting device, a time scheduling parameter, and a historical parameter related to the previous ranking score of the requesting device.

The missing bandwidth can be calculated by comparing the upper limit of the bandwidth of the requesting device with the bandwidth required for transmitting data to and/or receiving data from the requesting device when all data can be transmitted and/or received the amount. For example, if the requesting device is a monitoring device that acquires a video stream to be transmitted from the requesting device, a current bandwidth upper limit may need to be more beneficial than transmitting a video stream without visible compression artifacts or the like The higher the bit rate of the encoded video stream is reduced. In this case, the requesting device may calculate a desired bandwidth upper limit and the difference between the desired bandwidth upper limit and the current bandwidth upper limit. According to some embodiments, this amount of lost bandwidth is used to calculate the amount of increased bandwidth of the requesting device's bandwidth upper limit.

The importance parameter may reflect a parameter manually input from a user, for example, indicating that the requesting device is important and therefore should always have a comparison with other devices in the system One of the upper bandwidth limit.

If a specific device is more important or less important than other devices in the system during a specific time during the day, during the weekend, etc., then the scheduling parameter can be used. Other possible parameters or values for determining the ranking score of the requesting device will be described below.

According to some embodiments, the plurality of devices are each a monitoring device that obtains a respective monitoring data, wherein at least one of the following is used to calculate the ranking score of the requesting device and/or the ranking score of a remaining device: ˙Describe a content of the monitoring data One of the time parameters in the event is a complexity parameter that describes the complexity of the content of the monitoring data.

The monitoring data can be a video stream or an audio stream. In such a system that includes monitoring devices that transmit monitoring data, the monitoring data can be encoded by using different compression ratios and/or the bits of the monitoring data can be discarded when the monitoring data is encoded so that the control is required to transmit the encoded data. Bit rate and achieve the required bit rate reduction to control the bit rate of the transmitted data from a monitor to meet the upper bandwidth limit of the monitoring device. However, if the monitoring data includes a large number of events that are considered important (such as a large number of people in a video stream), then a lower bit rate reduction can be expected. Similarly, if the content of the monitoring data is complex, a higher bit rate reduction may be required to meet the upper bandwidth limit, which is undesirable because a large amount of data may be lost in encoding.

According to some embodiments, each of the plurality of devices has a lower bandwidth limit. In this case, when receiving the bandwidth from a device will cause the upper bandwidth limit of the device to be lower than the lower bandwidth limit, the bandwidth will not be received from the device. This can be achieved in different ways, for example by increasing the ranking score of this device or by including a lower bandwidth limit in the reply to the request from the requesting device and taking this limit into account when determining the device from which to receive the bandwidth. A further option may be that a remaining device that is close to or even (for some reason) lower than one of the lower bandwidth limit and one of the available bandwidth upper limit does not reply to the request from the requesting device.

According to some embodiments, when a new device is added to the system including the plurality of devices At the time of operation, the upper limit of the bandwidth of the new device is zero. This may cause the new device to start to request bandwidth, which will cause the available bandwidth of the system to be redistributed among the multiple devices including the new device without the combined bandwidth limit of the devices in the system exceeding the bandwidth limit of the system Risk.

In a second aspect, the invention provides a computer program product that includes a computer-readable storage medium having instructions adapted to perform the method of the first aspect when executed by a device with processing capabilities.

In a third aspect, the present invention provides a device interconnected with one or more other devices in a point-to-point network, the device has an adjustable upper limit of bandwidth, the device is adapted to: calculate an instruction to increase the frequency A ranking score of one of the priorities of the wide upper limit; a request for one of the additional bandwidth is sent to the one or more other devices; and one or more answers are received from the one or more other devices.

Each of the one or more answers corresponds to a respective one of the one or more other devices and includes a ranking score that describes one of the other devices that maintains a priority of the bandwidth upper limit of the other device.

The device is further adapted to determine, based on the ranking score and the ranking score of the one or more answers, one of the one or more other devices corresponding to the one or more received answers from which the bandwidth is received.

The device is further adapted to increase the upper bandwidth limit and sends a message to the determined device instructing the determined device to decrease the upper limit of the bandwidth of the determined device.

In a fourth aspect, the present invention provides a device interconnected with one or more other devices in a point-to-point network, the device has an adjustable bandwidth upper limit, the device is adapted to: from the one or One of the other devices requests the device to receive a request for bandwidth; calculates a ranking score indicating a priority to maintain a bandwidth upper limit; sends an answer to one of the requests for additional bandwidth, the answer including the ranking score; Receive a message with a command to reduce the upper limit of the device's bandwidth; and respond to reduce the upper limit of the bandwidth accordingly.

According to some embodiments, the device according to the third aspect and/or the fourth aspect may be a monitoring device that obtains monitoring data.

The second aspect, the third aspect, and the fourth aspect may generally have the same features and advantages as the first aspect.

100‧‧‧System

102‧‧‧Remote server

104a‧‧‧Video camera

104b‧‧‧Video camera

104c‧‧‧Video camera

104d‧‧‧Video camera

200‧‧‧ point-to-point network

202a‧‧‧device/request device

202b‧‧‧device/remaining device/answering device

202c‧‧‧device/remaining device/answering device/judgment device

202d‧‧‧device/remaining device/answering device

300‧‧‧Method

402‧‧‧Broadband request/broadcast message

502b‧‧‧Answer

502c‧‧‧Answer

502d‧‧‧answer

602‧‧‧Message

604‧‧‧ dotted line

606‧‧‧line/adjusted bandwidth limit

608‧‧‧ dotted line

610‧‧‧line/adjusted bandwidth limit

612a‧‧‧Box

612c‧‧‧Box

614‧‧‧ dotted line/lower bandwidth limit

616‧‧‧ dotted line/lower bandwidth limit

702‧‧‧ installation

702a‧‧‧Camera

702b‧‧‧Camera

702c‧‧‧Camera

704‧‧‧Central storage

706‧‧‧ processor

708‧‧‧Digital network module

S301‧‧‧Step

S302‧‧‧Step

S304‧‧‧Step

S306‧‧‧Step

S308‧‧‧Step

S310‧‧‧Step

S312‧‧‧Step

Through the following illustrative and non-limiting detailed description of embodiments of the present invention, reference to the accompanying drawings in which the same element symbols will be used for similar elements will better understand the above and additional objectives, features, and advantages of the present invention, among which: Fig. 1 shows a prior art system in which one of the video cameras of the system can be dynamically adjusted and determined by a server, Fig. 2 shows a plurality of devices interconnected in a point-to-point network, and Fig. 3 shows 2 is a method of negotiating bandwidth in a peer-to-peer network. Figure 4 shows by example how a request for one of the bandwidth is transmitted from a requesting device to the remaining devices in the peer-to-peer network. Figure 5 shows by example an example of bandwidth. The answer to the request is transmitted from the remaining device to the requesting device. FIG. 6 shows by way of example how to increase the bandwidth upper limit of a requesting device and how to decrease the bandwidth upper limit of a determined device. FIG. 7 shows the inclusion of a central storage A system in which video cameras storing their respective video streams are stored. FIG. 7 further describes this video camera.

FIG. 2 is a schematic example of a system including a plurality of devices 202 a to 202 d interconnected in a point-to-point network 200. This network 200 removes the need for a centralized server for sharing resources (eg, processing power, disk storage, or network bandwidth) between the devices 202a to 202d.

One of the further advantages of the point-to-point network 200 is that the point-to-point protocol used can have A routine used to deal with the loss of a device in a convenient and reliable manner (for example, if a device ceases to function or is otherwise disconnected from the network) and a newly added device in the peer-to-peer network 200. The system will therefore be able to continuously adapt to changes in the system.

Hereinafter, a method for negotiating bandwidth in one system including a plurality of devices 202a to 202d interconnected in the point-to-point network 200 will be described.

As described above, the devices 202a to 202d in the system can share the network bandwidth. However, the method for negotiating bandwidth described below can be applied to any type of network or system with bandwidth limitations. The bandwidth can be limited, for example, by one of the system's storage solutions or the actual network capacity of the system. Network capacity may be related to both downlink capacity and/or uplink capacity. For example, if the system includes multiple mobile phones requesting video streaming on a limited bandwidth system, the bandwidth limit is related to the downlink capacity of the system. If, on the other hand, the system includes a monitoring device that acquires monitoring data to be transmitted to a server for storage, the bandwidth limitation is related to the uplink capacity of the system or the amount of data that the server can store per unit of time.

The arrows in FIG. 2 describe that each of the plurality of devices 202a to 202d can communicate with each other. The arrows in Fig. 2 represent the possibility of communication. Other communication routing is possible, for example, if the device 202a communicates with the device 202d, it may send a message through the device 202c or through the device 202b instead of directly to the device 202d.

FIG. 3 shows a method for negotiating bandwidth in the point-to-point network 200 of FIG. Each of the devices 202a to 202d interconnected in the point-to-point network has a local bit rate controller that controls the bit rate of the individual devices 202a to 202d. Each of the devices 202a to 202d further has an adjustable bandwidth upper limit that sets one of the maximum bit rates of the data that the devices 202a to 202d can transmit or receive. When the bit rate of the data of a device 202a to 202d is close to the upper limit of the bandwidth, the device may send a request for additional bandwidth to one or more remaining devices of the plurality of devices 202a to 202d. Therefore, the first step of the method of FIG. 3 is to determine S301 whether any of the devices 202a to 202d needs more bandwidth. Therefore, each device 202a to 202d individually completes to make. If one of the plurality of devices 202a to 202d interconnected in the point-to-point network needs more bandwidth, this device (ie, one of the plurality of devices requesting the device) performs steps S302 to S310 shown in FIG. 3. The requesting device therefore calculates a ranking score of S302 instructing to increase the priority of the bandwidth upper limit of the requesting device. This calculation will be further described below in conjunction with FIG. 4. The next step in method 300 is to request the device to send S304 a request for one of the extra bandwidth to one or more remaining devices of the plurality of devices. This means that the requesting device sends the request to, for example, all other devices or at least some devices in the peer-to-peer network. Subsequently, the requesting device receives S306 one or more answers from one or more remaining devices, where each of the one or more answers corresponds to a respective one of the one or more remaining devices. According to some embodiments, an answer is received from each of the remaining devices in the peer-to-peer network, but for different reasons, some answers may not be received or sent by a remaining device. For example, the transmission of data through a communication network may result in the loss or loss of data packets, which means that the requesting device may not receive the data packet in which an answer was sent.

Each of the answers received by the requesting device includes a ranking score describing one of the remaining devices that maintains a priority of one of the bandwidth upper limits of the remaining devices. This ranking score and its calculation will be described further below.

The next step in method 300 is to request the device to determine S308 from which device the bandwidth is received. This determination is completed based at least on the ranking score of the requesting device and the ranking score of one or more answers. For example, the requesting device may determine that the device with the lowest ranking score should be the device from which it receives the bandwidth. According to some embodiments, if all the answers have a ranking score higher than the ranking score of the requesting device, the device from which the bandwidth is received will not be determined and the upper limit of the bandwidth of the requesting device will be left as it is.

However, if the requesting device determines that the bandwidth should be received from one of the remaining devices, the next step in the method 300 is to increase the bandwidth upper limit of the S310 requesting device, which can be done by the local rate controller of the requesting device, and Reducing the upper limit of the bandwidth of the determined device from which S312 receives the bandwidth, this can be done by the local rate controller of the determined device.

Since the required bandwidth of each of the devices used for interconnection in the point-to-point network can be dynamically changed, if it is determined S301 that another device or the same device that just obtained an increased bandwidth limit requires more bandwidth, then The method 300 can be restarted again.

4 illustrates by way of example how a request for a bandwidth 402 is transmitted from a requesting device 202a as a broadcast message 402 in a peer-to-peer network 200. Broadcasting refers to the transmission of a packet to be received by each device in the network (for example, from devices 202b to 202d). Compared with other methods of transmitting messages (for example, unicast or multicast), when the message is transmitted as a broadcast message, the address of the device receiving the message is not required. It should be noted that according to some embodiments, another way of transmitting a request for bandwidth (eg, unicast or multicast for a request for bandwidth) is used instead of utilizing a broadcast message.

The requesting device 202a therefore sends a request for one of the additional bandwidth to one or more other devices. Each of the remaining devices 202b to 202d therefore receives a request 402 for bandwidth from the requesting device 202a. The bandwidth request 402 may include information about the requesting device 202a. According to some embodiments, the request 402 includes an identifier of one of the requesting devices 202a. This can be advantageous because one of the responses 502b to 502d from one of the remaining devices 202b to 202d can be a unicast message in the peer-to-peer network 200. This embodiment is described in FIG. 5, where each of the one or more answers 502b to 502d is a unicast message in a peer-to-peer network. In FIG. 5, each of the one or more answers 502b to 502d corresponds to each of the one or more remaining devices 202b to 202d and is directly addressed to the requesting device 202a. According to other embodiments, the answer is also a broadcast message, which may be advantageous because all the devices in the peer-to-peer system 200 can learn the information in the answers from each of the answering devices 202b to 202d (eg, answering devices 202b to 202d The ranking score of each). In FIG. 5, all devices 202b to 202d that receive the request 402 (as described in FIG. 4) send an answer 502a to 502d to the requesting device. However, according to some embodiments, the request 402 for additional bandwidth includes the ranking score of the requesting device 402. In this case, a response to a request for additional bandwidth from a specific residual device of one or more residual devices has a high ranking score in the requesting device In the case of a ranking score of a specific remaining device, it may be sent only from the specific remaining device.

The requesting device is thus adapted to calculate a ranking score indicating a priority of increasing the upper limit of the bandwidth. The ranking score of the requesting device 202a can be calculated based on a variety of different parameters. This parameter may be the amount of bandwidth that the local element rate controller determines is capable of transmitting or receiving data in a favorable manner. For example, if the device is to receive a mobile phone that must be received in a very compressed state to satisfy a video stream with a bandwidth limit, the local rate controller may determine that an increase in the bandwidth limit will be beneficial. And also determine the amount of lack of bandwidth.

The ranking score of the requesting device 202a may be further based on the current bandwidth limit of the requesting device.

The ranking score of the requesting device 202a may be further based on an importance parameter of the requesting device in a system including a plurality of devices. For example, if the device is a monitoring device that obtains monitoring data, a device that is positioned from a monitoring point of view and directed toward an important monitoring location may have a high importance and therefore have an important parameter that reflects this. This may therefore lead to a higher ranking score if a device with an importance parameter with a high value requires more bandwidth. This importance parameter may reflect manual input from a user or may be calculated automatically.

For example, in a case where the device is considered to be more or less important in the system of the device during a specific time of day or night, or on a specific working day or month, etc., the ranking score of the requesting device 202a may be further based on a time scheduling parameter.

The ranking score of the requesting device 202a may be further based on a historical parameter related to the previous ranking score of the requesting device.

For example, in the case where the device is battery-powered and a power shortage is expected soon, the ranking score of the requesting device 202a may be further based on the event. In this case, it may be critical to quickly transfer any data collected or stored at the device to some other location for storage. Such a device may, for example, be a network attached storage (NAS) with an uninterruptible power supply (UPS).

In the case where the requesting device 202a is a monitoring device that acquires monitoring data, the ranking score may be based on the event of the acquired data, for example, an event parameter describing an event in a content of the monitoring data. For example, if the device acquires a monitoring camera that shows a person of interest or shows that a crime has occurred or generally includes only events that can be of interest from a monitoring point of view, this may result in a higher ranking score.

The ranking score can also be calculated based on a complexity parameter that describes the complexity of the content of the monitoring data. Since this complexity may result in an increased compression ratio and/or more bits are discarded when encoding monitoring data to meet the bandwidth upper limit, it may be advantageous to increase the ranking score of the requesting device to make the bandwidth upper limit more likely to increase .

Each of the remaining devices 202b to 202d is adapted to calculate a ranking score indicating a priority of maintaining a bandwidth upper limit. The ranking score of a remaining device (ie, devices 202b to 202d in FIGS. 4 to 6) can be calculated in a similar manner, for example, based on at least one of the following:-indicating a value of excess bandwidth of one of the remaining devices,-remaining devices The upper limit of the bandwidth,-an important parameter of the remaining devices in the system including a plurality of devices,-a time scheduling parameter,-a historical parameter related to the previous ranking score of the remaining devices.

For example, if a remaining device 202b to 202d has unused bandwidth (ie, the upper bandwidth limit is higher than, for example, the bandwidth actually required for receiving or transmitting data), this may result in a lower ranking score. The ranking score of a remaining device 202b to 202d may be further based on events at or collected by the device, as described above in connection with requesting the device.

This indication of excess bandwidth may be further included in a reply 502b to 502d sent from a remaining device 202b to 202d to the requesting device 202a. In other words, each of the one or more answers 502b to 502d may further include a value indicating an excess bandwidth at the remaining devices 202b to 202d corresponding to the answer. This value(s) can be used at the requesting device 202a to determine whether one or more of the remaining devices corresponds to one or more received answers 502b to 502d A device 202c from which bandwidth is received among 202b to 202d. This is depicted in Figure 6. If one of the excess bandwidth indications is included in the answers 502b to 502d, the determination may be based on these values. However, the determination of the device from which the bandwidth is received is based at least on the ranking score of the requesting device and the ranking score of one or more answers. By also including the excess bandwidth at the remaining device, even if it is determined that the ranking score of the device is not the lowest among the received answers, the bandwidth is still received from the device with this excess bandwidth. According to some embodiments, if receiving includes more than one answer indicating a value above one of the excess bandwidth, the step of determining at the requesting device 202a from which one of the available bandwidth devices is received includes selecting among more than one answer Answer with one of the lowest ranking score. The device from which the available bandwidth is received may be the device corresponding to the answer with the lowest ranking score. According to other embodiments, the device with the most excess bandwidth is selected as the device to receive the bandwidth from.

In FIG. 6, the device called 202c is determined as the device from which it should receive the bandwidth. In FIG. 6, the sizes of blocks 612a and 612c each represent the total amount of available bandwidth in a system including a plurality of devices 202a to 202d interconnected in a point-to-point network. In the left box 612c, the dashed line 608 represents one of the current bandwidth upper limits of the device 202c determined as the device from which bandwidth should be received. In the right box 612a, the dotted line 604 represents the current bandwidth upper limit of one of the requesting devices 202a. The requesting device increases the upper bandwidth limit until the level indicated by line 606, and sends a message 602 indicating that the determined device 202c decreases the upper limit of the bandwidth of the determined device to the determined device 202c. It is determined that the device 202c thus receives the message 602 with the instruction to reduce the upper limit of the bandwidth of the device 202c, and responds accordingly, reducing the upper limit of the bandwidth to the level indicated by the line 610.

According to some embodiments, the bandwidth upper limit of the requesting device 202a is increased by a predetermined amount, and the bandwidth upper limit of the determining device 202c is decreased by the same predetermined amount. This means that the bandwidth reallocation will usually be done in the repetition step, where a predetermined step in the bit rate (bandwidth) is used for each repetition. The request for bandwidth 402 may therefore not indicate the amount of bandwidth required, only an increase in request. The predetermined amount can be provided to the system by a user. The predetermined amount can be based on the total Available bandwidth (eg, total available bandwidth divided by 100, 50, or any other suitable number) and/or based on the number of devices interconnected in the point-to-point network. By way of example, the predetermined amount may be 0.5 Mbit/sec, 1 Mbit/sec or 3 Mbit/sec.

According to some embodiments, in order to determine the amount of bandwidth that the upper limit of the bandwidth at the requesting device will increase, one of the ranking score of the requesting device and the ranking score corresponding to the answer of the determined device from which the bandwidth is received may be calculated difference. Based on this difference, an amount of bandwidth received by the requesting device from the decision device can be calculated. This calculation may be further based on the total available bandwidth of the system, for example, by dividing the total available bandwidth by a suitable value based on the calculated difference. The calculated amount of bandwidth is then used to increase the upper limit of the bandwidth of the requesting device 202a and is further included in the message 602 sent to the determined device 202c that then decreases the amount by the upper limit of the bandwidth. This reallocation can also be repeated, but the amount of bandwidth to be received may differ between the two requests for bandwidth.

In addition, each of the plurality of devices may have a lower bandwidth limit, that is, dotted lines 614, 616 for the devices 202a, 202c, respectively. According to some embodiments, when receiving bandwidth from a device will cause the upper bandwidth limit of the device to be lower than the lower bandwidth limit, the bandwidth cannot be received from the device. This can be implemented in different ways, for example, by: if the current bandwidth upper limit of a remaining device is close to or lower than the lower bandwidth limit, the request for additional bandwidth is not answered; or in this case, the ranking score of the remaining device is increased ; Or even if there is excess bandwidth, it does not indicate any excess bandwidth. For the embodiment in FIG. 6, the adjusted upper bandwidth limits 606, 610 are above the lower bandwidth limits 614, 616.

As described above, one of the advantages of using a peer-to-peer network is that it handles newly added devices of the peer-to-peer network in a convenient and reliable manner. In order to allocate the available bandwidth to a newly added device, it is advantageous to set the upper limit of the bandwidth of the new device to zero. The native device rate controller of the new device can immediately determine that additional bandwidth is required, which in turn causes the new device to issue a request for additional bandwidth. At least depending on the respective ranking scores of the devices interconnected in the point-to-point network, the total available bandwidth of the system will be distributed among all such devices. If as above Using the iterative method as described in the above, it is possible to handle this allocation in one of the convenient ways in which more than one "old" device can contribute bandwidth to the new device.

As mentioned above, devices interconnected in a point-to-point network can be monitoring devices that each obtain a separate monitoring data. Examples of such devices are monitoring cameras for acquiring a video stream or monitoring microphones for acquiring an audio stream.

FIG. 7 describes, by way of example, a system including three cameras 702a to 702c interconnected in a point-to-point network 200. A camera 702a to 702c can be, for example, any type of camera that captures visual light (a thermal camera, a time-of-flight camera) or any other sensor array that captures a depth map, for example. Different types of cameras can be used in the same system.

In FIG. 7, each camera acquires a video stream stored in a central storage 704. The storage capacity (the amount of data that the storage 704 can store per time unit) is limited. This means that each camera 702a to 702c may need to encode the acquired video stream to achieve bit rate reduction, as described above. As also described above, a reduction in bit rate (via a bandwidth cap) can be negotiated between cameras based at least on the ranking score of each camera.

FIG. 7 further includes by way of example a schematic illustration of one of the devices 702 in the system. This illustration is not dedicated to a camera, but is a more general illustration of any device that can be interconnected with other devices in a peer-to-peer network as described herein. The device 702 includes a processor 706 that can be used for all calculations when negotiating bandwidth (eg, a device for calculating a ranking score and deciding from which bandwidth to receive). The processor 706 is also used for any calculation performed by the local rate controller as described above. The device 702 further includes a digital network module 708 for receiving and/or transmitting data (for example) to the central storage 704. The device 702 further includes a module for transmitting and receiving messages within the peer-to-peer network 200.

200‧‧‧ point-to-point network

702‧‧‧ installation

702a‧‧‧Camera

702b‧‧‧Camera

702c‧‧‧Camera

704‧‧‧Central storage

706‧‧‧ processor

708‧‧‧Digital network module

Claims (16)

A method (300) for negotiating bandwidth in a system including a plurality of devices (202a to 202d; 702a to 702c) that share bandwidth and interconnect in a point-to-point network (200), wherein Each of the plurality of devices has an adjustable upper bandwidth limit (606, 610). The method includes the following steps: calculating (S302) at a requesting device (202a) among the plurality of devices to instruct to increase the number of the requesting device A ranking score of one of the requesting devices with a priority of one of the upper limit of the bandwidth; a request (402) for one of the additional bandwidth will be sent (S304) from the requesting device to one or more of the plurality of devices Remaining device (202b to 202d); receiving (S306) at the requesting device one or more answers (502b to 502d) from the one or more remaining devices, wherein each of the one or more answers A ranking score of one of the remaining devices corresponding to each of the one or more remaining devices and including describing to maintain a priority of the bandwidth upper limit of the remaining device, based on the following at the requesting device It is determined (S308) one of the devices (202c) receiving bandwidth from the one or more remaining devices corresponding to the one or more received answers: the ranking score of the requesting device, and the one or more The ranking score of each answer; increase (S310) the upper limit of the bandwidth of the requesting device (606); and decrease (S312) the upper limit of the bandwidth of the determined device from which it receives the bandwidth (610). The method of claim 1, wherein the request for additional bandwidth is a broadcast message in the peer-to-peer network. A method as in claim 1 or 2, wherein the request for additional bandwidth includes the request An identifier of the device, and each of the one or more answers is a unicast message in the peer-to-peer network. The method of claim 1 or 2, wherein the step of increasing the bandwidth upper limit of the requesting device includes increasing the bandwidth upper limit by a predetermined amount, and wherein the step of decreasing the bandwidth upper limit of the determined device includes The upper limit of the bandwidth is reduced by the predetermined amount. If the method of item 1 or 2 is requested, it further includes the steps of: calculating a difference between the ranking score of the requesting device and the ranking score corresponding to the answer of the decided device from the receiving bandwidth; and Based on the calculated difference, an amount of bandwidth received by the requesting device from the determined device is calculated, wherein the step of increasing the bandwidth upper limit of the requesting device includes increasing the bandwidth upper limit by the calculated bandwidth And the step of reducing the upper limit of the bandwidth of the determined device includes reducing the upper limit of the bandwidth by the calculated amount of bandwidth. The method of claim 1 or 2, wherein each of the one or more answers further includes a value indicating an excess bandwidth at the remaining device corresponding to the answer, and wherein the determining at the requesting device The step of one of the one or more remaining devices corresponding to the one or more received answers from which the bandwidth is received is further based on: indicating the value of the excess bandwidth of one of the one or more answers. The method of claim 1 or 2, wherein at least one of the following is used to calculate the ranking score of a remaining device: a value indicating an excess bandwidth of the remaining device, the upper limit of the bandwidth of the remaining device, including the plural An importance parameter of the remaining devices in the system of a device, a time scheduling parameter, and a historical parameter related to the previous ranking score of the remaining device. As in the method of claim 1 or 2, wherein at least one of the following is used to calculate the ranking score of the requesting device: a parameter indicating a quantity of the lost bandwidth at the requesting device, the upper limit of the bandwidth of the requesting device, An importance parameter of the requesting device in the system including the plurality of devices, a time scheduling parameter, and a historical parameter related to the previous ranking score of the requesting device. A method as in claim 1 or 2, wherein the plurality of devices are monitoring devices (702a to 702c) each acquiring a respective monitoring data, wherein at least one of the following is used to calculate the ranking score and/or a remaining of the requesting device The ranking score of the device: an event parameter describing an event in a content of the monitoring data, and a complexity parameter describing the complexity of the content of the monitoring data. The method of claim 1 or 2, wherein each of the plurality of devices has a lower bandwidth limit (614, 616), and wherein when receiving bandwidth from a device will cause the upper bandwidth limit of the device to be lower than the When the bandwidth is lower, the bandwidth cannot be received from the device. The method of claim 1 or 2, wherein when a new device is added to the system including the plurality of devices, the upper bandwidth limit of the new device is zero. A computer program product comprising a computer-readable storage medium having instructions adapted to implement the method of any one of claims 1 to 11 when executed by a device with processing capabilities. A device (202a) with one available bit rate capacity for transmitting and/or receiving data, the device shares bandwidth with one or more other devices (202b to 202d) in a point-to-point network (200) Interconnected, the device has an adjustable bandwidth upper limit (604), the device is adapted to: calculate (S302) an order to increase a ranking score of a priority of the bandwidth upper limit; A request (402) for one of the extra bandwidth will be sent (S304) to the one or more other devices; one or more answers (502b to 502d) will be received (S306) from the one or more other devices, where the one Each of the one or more answers corresponds to each of the one or more other devices and includes a ranking score of one of the other devices that describes a priority that maintains the upper limit of the bandwidth of the other device; based on each of the following ( S308) one of the one or more other devices corresponding to the one or more received answers corresponding to the receiving bandwidth (202c): the ranking score, and the ranking score of the one or more answers; increase The upper bandwidth limit; and a message (602) instructing the determined device to decrease the upper bandwidth limit (610) of the determined device to the determined device. The device of claim 13 is a monitoring device configured to transmit the acquired monitoring data. A device (202c) with one available bit rate capacity for transmitting and/or receiving data, the device shares frequency with one or more other devices (202a to 202b, 202d) in a point-to-point network (200) Wide and interconnected, the device has an adjustable bandwidth upper limit (610), the device is adapted to: receive a request for additional bandwidth from a requesting device among the one or more other devices (402); calculate Instruct to maintain a ranking score of one of the priorities of the bandwidth upper limit; send an answer to one of the requests for additional bandwidth (502c), the answer includes the ranking score; and receive the bandwidth upper limit with the device reduced Message (602), and respond accordingly, reducing the upper limit of the bandwidth. The device of claim 15 is a monitoring device configured to transmit the acquired monitoring data.

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